Shoulder Pain with Exercise

Question:

I have a 41-year-old Caucasian male client whom I’ve been training for the past three months. Our sessions comprise purely strength training with free weights as his primary goal is upper body hypertrophy. I obviously include core conditioning work into his routine as well. Since I have begun training my client, he has experienced pain in his right shoulder. It appears to be the medial deltoid when he attempts to abduct his shoulder during exercises such as dumbbell flye and lateral raise. He tells me it feels as if there is a little ball where his shoulder (deltoid) meets his bicep. It doesn’t cause extreme pain; it’s more of an uncomfortable, limiting feeling – he complains of "tightness." He seems to think that it could be caused by repetitive use of the mouse while he sits at the computer all day (RSI). Do you have any suggestions as to what this could be?

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